29 C.F.R. § 801.14
(a) Section 7(e) of the Act provides an exemption from the general prohibition against polygraph tests for certain armored car, security alarm, and security guard employers. Subject to the conditions set forth in sections 8 and 10 of the Act and §§ 801.21, 801.22, 801.23, 801.24, 801.25, 801.26, and 801.35 of this part, section 7(e) permits the use of polygraph tests on certain prospective employees provided that such employers have as their primary business purpose the providing of armored car personnel, personnel engaged in the design, installation, and maintenance of security alarm systems, or other uniformed or plainclothes security personnel; and provided the employer's function includes protection of:
(1) Facilities, materials, or operations having a significant impact on the health or safety of any State or political subdivision thereof, or the national security of the United States, such as—
(b)
(d)
(2) The specific “facilities, materials, or operations” contemplated by this exemption include those against which acts of sabotage, espionage, terrorism, or other hostile, destructive, or illegal acts could significantly impact on the general public's safety or health, or national security. In addition to the specific examples set forth in the Act and in paragraph (d)(1) of this section, the terms would include:
(i) Facilities, materials, and operations owned or leased by Federal, State, or local governments, including instrumentalities or interstate agencies thereof, for which an authorized public official has determined that a need for security exists, as evidenced by the establishment of security requirements utilizing private armored car, security alarm system, or uniformed or plainclothes security personnel, or a combination thereof. Examples of such facilities, materials and operations include:
(ii) Commercial and industrial assets and operations which—
(iii) Public and private energy and precious mineral facilities, supplies, and reserves, including—
(iv) Major public or private transportation and communication facilities and operations, including—
(e)
(g)
(4) The scope of the exemption is not limited, however, to those security personnel having direct, physical access to the facilities being protected. Various support personnel may also, as a part of their job duties, have access to the process of providing security services due to the position's exposure to knowledge of security plans and operations, employee schedules, delivery schedules, and other such activities. Where a position entails the opportunity to cause or participate in a breach of security, an employee to be hired for the position would also be deemed to be “employed to protect” the facility.